Device for a sight

ABSTRACT

There is disclosed a compensating device for correcting errors in the traversing or elevating angles of the barrel of a gun emplaced on an uneven supporting surface. The device comprises a suspension for the gun barrel permitting traversing and elevating of the gun. The device further comprises a sight supported by a gimbal suspension which in turn is coupled to the gun barrel and the carriage therefor so that the gimbal will be in a horizontal position independent of turning of the gun barrel. The sight is further so arranged that its optical objective remains locked on to a selected reference point independent of elevating or traversing the gun barrel.

United States Patent 1 Johansson DEVICE FOR A SIGHT [75] Inventor:Arnold Johannes .lohansson,

Karlskoga, Sweden [73] Assignee: Aktiebolaget Boiors, Bofors, Sweden[22] Filed: Feb. 9, 1971 21 Appl. No.: 113,964

. [30] Foreign Application Priority Data FOREIGN PATENTS OR APPLICATIONS377,575 9/1939 Italy 89/41 T Primary Examiner-Stephen C. BentleyAttorney-Hana, Baxley & Spiecens [5 7] ABSTRACT There is disclosed acompensating device for correcting errors in the traversing or elevatingangles of the barrel of a gun emplaced on an uneven supporting surface.The device comprises a suspension for the gun barrel permittingtraversing and elevating of the gun. The device further comprises asight supported by a gimbal suspension which in turn is coupled to thegun barrel and the carriage therefor so that the gimbal will be in ahorizontal position independent of turning of the gun barrel. The sightis further so arranged that its optical objective remains locked on to aselected reference point independent of elevating or traversing the gunbarrel.

7 Claims, 2 Drawing Figures PAIENTEUuuvzo ms 3772.960

I Z FIGI k r I I INVENTOR. ARNOLD JOfi/ANNES JOHANSSON A T TOENE YsDEVICE FOR A srcnr The following invention relates to a sight for afield artillery gun or corresponding materiel, which has a gimbalsuspension on an axle arranged parallel with or coinciding with an axisof symmetry of a gun barrel, the gun also being provided with trunnionsuspension and pivot-shaft suspension for setting the angles ofelevation and traverse of the barrel.

A prominent object for a gun of this kind is that it should be possibleto use it for firing even if it is emplaced on a sloping or uneven base,without therefore having to re-calculate the set gun data for each andevery different inclination of the gun.

In order to solve this problem, it is necessary to provide the gun witha transformation system which allows the aiming movement of the gun tobe read off in a vertical-horizontal coordinate system. It is thenappropriate to arrange the sight to be in a vertical-horizontal positionregardless of how the gun is inclined or the barrel is turned around itspivot-shaft suspension. It is thus previously known to utilizetransformation systems for sights and guns as above, but the hithertoknown designs have in common that either a new manual horizontal settingof the sight is required for each traversing movement of the gun, ortechnically comparatively complicated devices are required whichautomatically perform such setting for each traversing movement. Thus,for instance, in several cases it has been proposed to utilize apendulum or a corresponding device which with the aid of electricalservos sets the sight horizontally, which involves the extremely greatdrawback that the gun will be dependent on an electric power supply.

The present invention solves the above-mentioned problem in that itrelates to a mechanical design which also has an extremely simpleconstruction. The feature that can primarily be considered tocharacterize a de vice according to the invention is that the sight, inaddition to having a gimbal suspension on an axle parallel with orcoinciding with an axis of symmetry of the bar rel of the gun is alsoconnected with a control member arranged in such a way that thecentering line for this and the pivot-shaft suspension either coincideor are parallel, in which latter case the control member which is thusat a predetermined radial distance from the pivot-shaft suspension alsofollows the angular movement of the barrel around the pivot-shaftsuspension. The control member is also given such a relativecounterrotation around its centering line in relation to the angularmovement of the barrel around the pivot-shaft suspension and is fastenedin such a way in the sight that this, at a given inclination of thepivot-shaft suspension in relation to a vertical plane, is sethorizontally independent of the turning of the barrel around thepivot-shaft suspension. In addition the control member and/or itsfastening means in the sight are adjustable for setting the sighthorizontally for different inclinations of the pivot-shaft suspension.

Through the utilization of the invention it also becomes possible, forinstance, that an objective located on the sight can be given acounter-rotation in relation to the angular movement of the barrelaround the pivot shaft suspension, so that, independent of such angularmovement, the objective is kept directed towards the reference pointused for the aiming of the gun. Thus, a great advantage is obtained inthat, for instance, when setting a new angle of traverse, it is notnecessary to first turn the objective in the opposite direction to anangle corresponding to said angle of traverse and thereafter, byregulating the setting members of the gun to look for the aiming pointin question in the objective. This has not been possible with previouslyused transformation systems.

An embodiment presently proposed which has the characteristics that aresignificant for the invention will be described in more detail withreference to the attached drawings, in which FIG. 1 shows a horizontalview of'a gun with a sloping emplacement and on which a sight is fitted;and

FIG. 2 shows a vertical view, partly in cross section, of the gunaccording to FIG. 1.

In FIG. 1, is shown a gun I, with a barrel 2. In order to enable thebarrel to be set at selected angles of elevation and traverse, the gunis also provided with a trunnion 3 and a pivot-shaft suspension, whichis not shown in FIG. 1. If the gun is emplaced horizontally, i.e., sothat its upper carriage 4 has a horizontal position, the setting of theangle of elevation will be set by turning the barrel in the trunnion,while the angle of traverse is set by turning the barrel around thepivot-shaft suspension.

Further, a sight 5 is mounted by a gimbal suspension on an axle 6 whichis parallel with an axis of symmetry 7 of the barrel 2 of the gun, and abracket having two arms 8 which is rotatable around the axis 6. Thesight is also connected to a control member 9, which is fastened to thesight at one end 9a. As may be noted from the figure, that the sight hasan eyepiece in the form of an ocular 10, a rotatable objective means 11and a transmission between the control member 9. and the objective 11 inthe form of a parallelogram of which links 12 and 12a are indicated. Theparallelism of the axle 6 to the barrel is obtained in that it in turnis supported in a further bracket 13 which is connected to the barrel inthe trunnion suspension, which, further bracket follows the turning ofthe barrel around the trunnions.

In FIG. 2, a journal comprised in the pivot-shaft suspension isdesignated 14, and a centering line of the control member 9 isdesignated 15. The control member 9 is arranged on the gun in such a waythat centering line 15 is parallel with the pivot-shaft suspension, moreparticularly with the line of symmetry 16 of this suspension. Thecontrol member is placed at an appropriate radial distance from the lineof symmetry 16 and the member is also arranged in such a way on the gunthat it follows the angular movement of the barrel around thepivot-shaft suspension. The radial distance is predetermined inconjunction with the designing of the gun.

The fastening device between the sight and the control member has aspherical surface 17 located at end 9a of the control member 9, whichcsoacts with a recess in a circular part 18. This part is supported atits periphery in a groove in the sight so that it can turn around itsaxis of rotation. The fastening device also has a locking member of aknown. kind, not shown, which clamps the spherical surface to thesurface of said recess. By actuating the locking; member, it is thuspossible to release the clamping and set the part 18 horizontal in casethe inclination of the control member (gun) should be changed. Thishorizontal setting can be made with the aid of, for instance, a spiritlevel, not shown. Finally, the control member is fastened at its otherend 9b to a transmission in the form of a parallelogram, which comprisestwo link arms, one of which 19 is firmly fixed in the control member 9,and the other one 20 is supported in a lower carriage of the gun whichis not shown. By means of this arrangement the control member can begiven such a relative counterrotation around its centering line 15 inrelation to the angular movement of the barrel around the pivot-shaftsuspension 14 that, together with the fastening device described betweenthe control member and the sight, it causes the sight, if the part 18 isset horizontal for a given inclination of the pivot-shaft suspension inrelation to a vertical plane, at said given inclination to remainhorizontal independent of the turning of the barrel around thepivot-shaft suspension. In the example of the embodiment the actualrotation of the control member will be zero, even if the control memberturns around the centering line 15 in relation to, for instance, theupper carriage 4, as this movement is directed pposite to and has thesame rotating speed as the rotation of the journal 14.

From FIGS. 1 and 2 it will be noted, in accordance with the above, that,for instance, the upper surface of the sight rotates in its horizontalplane when the barrel is turned around the pivot and trunnionsuspensions at the same time as the sight and the control member arerotated in relation to each other, and this latter rotation can beutilized for a device for measuring angles of traverse which is locatedin an appropriate place on the sight. It will also be noted from theFigures that the bracket arms 8 move in relation to the sight independence of how the barrel is turned around the suspensions. Thisrotating movement of the bracket can be utilized in a device formeasuring angles of elevation, and both this measuring device and thedevice for measuring angles of traverse are provided with scales. It isthen possible, in spite of a possible inclination of the gun, to obtaina setting of the barrel which actually corresponds to the values givenin a range table for elevation and traverse, which values can thus beindicated in the sight without having to re-calculate these or having tomake a new horizontal setting.

In the figures it has also been indicated symbolically that theobjective 11 is actuated by the rotating movement of the part 18 whichis obtained between the control member and the sight via a parallelogramof a known kind, comprising inter alia the links 12 and 120, by means ofwhich parallelogram a counter-rotation of the objective is achievedwhich keeps it on the reference point A used for setting the angle oftraverse of the gun even when a movement of the barrel causes the sightto turn in its horizontal plane. This gives the possibility of settingnew values ordered in the sight at the same time the setting of thebarrel can take place. If, again, a transmission of such a simple kindas the para]- lelogram shown is then chosen, it is advisable to make itdisengageable, so that the objective can be locked on the sight when theangle of traverse desired has been set. A possibility is therebyobtained for making fine adjustments, in which the objective can begiven an exact setting on the reference point.

In the figure there is also shown a circle 21. A perpendicular linethrough the fastening point 22 would move on the upper carriage if thegun is rotated one full turn around thepivot-shaft suspension. In everyposition of the barrel on the suspension the inclination of the gun canbe read off in a conceived coordinate systemfor the gun, for instance,through the intersection point of the control member in the uppercarriage 4. A component 23 shows the inclination in traverse and acomponent 24 the inclination in elevation.

The invention is not limited to the embodiment shown above as anexample, but can be subject to modifications within the scope of thefollowing claims.

The axle 6 on which the shaft is arranged can, for instance, be allowedto coincide with the axis of symmetry of the gun barrel, and the bracketarm 13 will then have a different extension. It is also conceivable tohave the control member 9 located so that its centering line coincideswith the pivot-shaft suspension and the fastening device between thesight, and the control member can very well be made differently and thenhave a ball joint, a universal joint or a bend in the control member atits fastening end, etc. The transmissions shown in the form ofparallelograms, which can be used for guns with limited aiming movementscan, of course, be replaced by, for instance, gear transmissions.Furthermore, it should also be mentioned that even if the functioning issimplified to an optimum as regards relative counter-rotation,fastening, etc., variations of this kind are within the scope of theconcept of the invention.

I claim:

1. A compensating device for correcting errors in the traversing orelevating angles of the barrel of a gun emplaced on an uneven supportingsurface, said device comprising: suspension means including a pivotshaft supporting the gun barrel for traversing the same, suspensionmeans including a trunion supporting the gun barrel for elevating thesame, sighting means, gimbal suspension means supporting the sightingmeans, a shaft disposed parallel to an axis of symmetry of the barrelsupporting the gimbal means, a control bar attached at one end to saidsighting means in a position such that a centering line for the sightingmeans and the pivot shaft is parallel in which case the control bar isheld at a predetermined radial distance from the pivot shaft, saidcontrol bar following angular movements of the barrel about said pivotshaft and also performing a relative counter rotation about saidcentering line in relation to the angular movements of the barrel aboutsaid pivot shaft, the attachment of said one end of the control barbeing such that for a given inclination of the pivot shaft relative to avertical plane, the sighting means occupies a horizontal positionindependent of traversing of the barrel about said pivot shaft, saidcontrol bar being pivotal for setting the sighting means in thehorizontal position for selected different inclinations of the pivotshaft.

2. The compensating device according to claim 1 and comprisingadjustable fastening means for retaining the sighting means in aselected position thereof, said fastening means including a sphericallycurved surface at the end of the control bar supported by the sightingmeans and a matchingly curved recess in a member supported by thesighting means, said curved surface of the control bar being inengagement with said recess for swivelling the control bar.

3. The compensating device according to claim 2 wherein said fasteningmeans are in the form of a ball joint at the end of the bar engaged withsaid recess.

4. The compensating device according to claim 1 and comprisingtransmission means coupling the other end of the control bar to astationary part of a carriagefor imparting to the objective means arotation in opposition to a pivoting of the gun barrel about the pivotshaft for maintaining the objective means in a position trained upon aselected reference point independent of elevating or traversing of thegun barrel.

7. The compensating device according to claim 6 wherein saidtransmission means comprise a parallelogram means coupling the objectivemeans to the control bar.

1. A compensating device for correcting errors in the traversing orelevating angles of the barrel of a gun emplaced on an uneven supportingsurface, said device comprising: suspension means including a pivotshaft supporting the gun barrel for traversing the same, suspensionmeans including a trunion supporting the gun barrel for elevating thesame, sighting means, gimbal suspension means supporting the sightingmeans, a shaft disposed parallel to an axis of symmetry of the barrelsupporting the gimbal means, a control bar attached at one end to saidsighting means in a position such that a centering line for the sightingmeans and the pivot shaft is parallel in which case the control bar isheld at a predetermined radial distance from the pivot shaft, saidcontrol bar following angular movements of the barrel about said pivotshaft and also performing a relative counter rotation about saidcentering line in relation to the angular movements of the barrel aboutsaid pivot shaft, the attachment of said one end of the control barbeing such that for a given inclination of the pivot shaft relative to avertical plane, the sighting means occupies a horizontal positionindependent of traversing of the barrel about said pivot shaft, saidcontrol bar being pivotal for setting the sighting means in thehorizontal position for selected different inclinations of the pivotshaft.
 2. The compensating device according to claim 1 and comprisingadjustable fastening means for retaining the sighting means in aselected position thereof, said fastening means including a sphericallycurved surface at the end of the control bar supported by the sightingmeans and a matchingly curved recess in a member supported by thesighting means, said curved surface of the control bar being inengagement with said recess for swivelling the control bar.
 3. Thecompensating device according to claim 2 wherein said fastening meansare in the form of a ball joint at the end of the bar engaged with saidrecess.
 4. The compensating device according to claim 1 and comprisingtransmission means coupling the other end of the control bar to astationary part of a carriage for the gun barrel to effect said counterrotation of the control bar whereby the actual rotation of the controlbar is zero.
 5. The compensating device according to claim 4 whereinsaid transmission means comprises a parallelogram.
 6. The compensatingdevice according to claim 1 wherein said sighting means comprise arotatable optical objective means and transmission means coupling saidobjective means to the control bar, said control bar imparting to theobjective means a rotation in opposition to a pivoting of the gun barrelabout the pivot shaft for maintaining the objective means in a positiontrained upon a selected reference point independent of elevating ortraversing of the gun barrel.
 7. The compensating device according toclaim 6 wherein said transmissioN means comprise a parallelogram meanscoupling the objective means to the control bar.